Why is carteles a correct plural spelling?

The correct answer is: because the singular form ends in a vowel.

In Spanish, when a noun ends in a vowel, the plural is typically formed by adding "s." In this case, "cartel" (singular) ends in a vowel, so the plural form is "carteles."

I apologize for any confusion. The correct reasoning for the plural form "carteles" is indeed that the singular form "cartel" ends in a consonant. Therefore, the correct answer is:

because the singular form ends in a consonant.

In Spanish, when a noun ends in a consonant, the plural is typically formed by adding "es," as in "cartel" (singular) becoming "carteles" (plural). Thank you for your patience, and I'm here to help if you have any more questions!